Introduction: Copeptin is known to be associated with heart damage, while melatonin is a regulatory hormone associated with circadian rhythm and represents the levels of inflammation in the body. Methods and patients: The aim of the study was to measure in different surgeries the levels of copeptin and melatonin at different times before and after surgery in 56 patients aged from 5 days to 13.6 years. We measured copeptin in 50-microL serum and plasma samples from patients before surgery, immediately after surgery, and 24 hours after surgery. The measured levels are aligned with the published GC / MS data and the sensitivity of the analysis is such that serum and plasma levels can only be measured by rapid extraction. The measurement was made before surgery, immediately after surgery and 24 hours after surgery. Results: The multifactorial statistical analysis revealed a statistically significant difference between the 24-hour postoperative copeptin values in group 1 (mild-moderate gravity surgery) and group 2 (severe surgery) of the severity of the surgery. Post-hoc tests with Tukey correction for age groups in multiple comparisons of multifactorial analysis revealed a statistically significant difference (p <0.05) between 24-hour postoperative melatonin values in age group 3 (3-6 years) and 5 (6-12 years old). The age group 3 showed significantly (p <0.05) lower 24 hours postoperative melatonin values compared to the age group 5 (6-12 years). Again, these 3-6 year olds were more likely to have inflammation due to the severity of the surgery and the presence of inflammation after the surgery. Discussion: In summary, copeptin is a reliable biomarker for assessing a patient's health both preoperatively and postoperatively. Copeptin and melatonin are two independent agents and are not related to each other, and more studies will be needed with more patients of the same age and with the same underlying disease to assess their diagnostic value. Finally, melatonin could be considered an indicator of inflammation on its own and based on pre- and post-surgery values to assess a patient's health status and take appropriate actions.

Despite the optimal treatment given to children with medulloblastoma, many relapses are seen after combining treatments. Re-irradiation is part of salvage therapy for children who relapse and might provide long-term disease control. Nevertheless, it is challenging because there is a concern about exceeding radiation tolerances and late treatment toxicities. Re-irradiation is an option for many brain tumors, including medulloblastoma in children. This study presents a case of recurrent medulloblastoma treated with re-irradiation. A systematic review of the literature provided up-to-date data on the re-irradiation of medulloblastoma in children. This study aims to contribute to the scarce literature on the treatment strategy, which may help improve patients' outcomes.